Technical Field
The present disclosure generally relates to the technical field of manufacture of the radiation imaging checking equipments, and specifically relates to the vehicle traction apparatus and a radiation imaging checking system.
Description of Related Information
A radiation imaging checking system is necessary for detection equipments of the customs, airports and railways. The checking equipments include a detection channel, and a radiation source and an array detector mounted within the detection channel. When a vehicle to be detected(for example, a vehicle loaded with containers) passes through the detection channel and passes the radiation source, a ray beam emitted by the radiation source penetrates through the vehicle to be detected, and is received by the array detector. The array detector is adapted for converting an intensity of the ray beam to gray-scale of an image, thereby obtaining a transmission image of objects loaded in the vehicle to be detected.
At present, generally by use of a vehicle traction apparatus, front wheels of the vehicle to be detected are fixed, and the vehicle to be detected is dragged to move and pass through the detection channel. Conventional vehicle traction apparatus can be divided into two types, and one type of the vehicle traction apparatus disposes tracks and a traction wagon under the ground, to avoid the traction wagon from shadowing the vehicle to be detected and thus affecting a detection result. However, installation of this type of the vehicle traction apparatus relates to civil construction and equipments installation, wherein the civil construction has a large scale, resulting in high production and usage cost and inconvenient maintenance.
Other type of the vehicle traction apparatus has a structure as shown in FIG. 1, and includes two parallel tracks (not shown in FIG. 1), two front fork arms 1, two rear fork arms (not shown in FIG. 1), lifting mechanism 3 and rotary driving mechanism (not shown in FIG. 1). The tracks are disposed on a ground; the two front fork arms 1 are respectively disposed on an inner side of the two tracks; and the two rear fork arms are respectively disposed on an inner side of the two tracks, and spaced apart from a respective front rear fork arm in a direction parallel to the tracks. The number of the rotary driving mechanism is four, and each of the rotary driving mechanism is used for driving a corresponding one of the two front fork arms 1 and two rear fork arms to rotate around a rotary shaft 4, to a position (a position as shown in FIG. 1) where the corresponding one of the two front fork arms 1 and two rear fork arms is perpendicular to the track for fixing the front wheels of the vehicle to be detected, or to a position where the corresponding one of the two front fork arms 1 and two rear fork arms is parallel to the track in order for the vehicle to be detected to pass. The number of the lifting mechanisms 3 is four, and each of the lifting mechanism 3 is disposed on an outer side of a corresponding one of the two front fork arms 1 and the two rear fork arms, for driving the two front fork arms 1 and the two rear fork arms to move up or down synchronously.
This type of the vehicle traction apparatus is disposed on the ground, and thus the civil works and production and usage cost can be reduced. However, there is an inevitable problem during usage:
In this vehicle traction apparatus, four lifting mechanisms individually drives the two front fork arms and the two rear fork arms to move up and down, the footprint is large and the cost is high. Moreover, since each of the lifting mechanism 3 is disposed on the outer side of a corresponding one of the two front fork arms 1 and the two rear fork arms, the lifting mechanism 2 with a higher height will shadow a bottom of the vehicle to be detected when it is prospectively imaged, and the shadowed area is large. Thus, the imaging effect and imaging scope of the vehicle to be detected will be affected adversely.